The death of the analogue television set was officially confirmed today, nearly 85 years after John Logie Baird held his first public display of the capabilities of the box in the corner of the living room that has tranformed our lives.

All the major high street electronics retailers have now stopped selling analogue sets after quietly running down their stocks in recent months, in preparation for the switch to digital terrestrial television (DTT) by 2012.

Last month, for the first time, there were no sales of analogue TV sets in the UK, according to figures published today by the organisation responsible for helping viewers switch, Digital UK.

With 5 million homes now transferred to a DTT-only signal and 11 million more due to switch by the end of 2011, new analogue TV sets are of little use to viewers.

And even though the process of turning off the analogue terrestrial television signal region by region across the UK will continue for two more years, in practice switchover has already nearly been achieved.

The north of Scotland is currently being switched, with central Scotland and the Channel Islands following later this year. But next year will be even busier with 11 million homes converting in Yorkshire, the West Midlands and the east of England.

London, the south east, Tynes Tees and Ulster will be the last regions to switch in 2012.

There have only been a couple of glitches – some viewers have struggled to retune their set-top boxes and in some parts of the north west, viewers got Welsh television when their region's analogue transmitter was switched off.

The Digital UK chief executive, David Scott, said: "People like digital television. It's still early days for TV switchover but there is clear evidence that the benefits of digital TV are welcomed by the vast majority of those who have upgraded, most of whom found it a straightforward process."

With the switch going more smoothly than expected and by working closely with local charities to let vulnerable viewers know what was happening, rather than running long expensive national advertising campaigns, Digital UK has a projected £55m surplus from its budget that will be handed back to the government in 2012.

In 2005, it was allocated £201m to fund nationwide switchover communications campaigns telling people when their region was being switched from analogue to digital and how to deal with it.

Digital UK's surplus is in addition to the £250m expected to be left over from the so-called "digital help scheme", a pot of money set aside from the BBC licence fee to pay for the most vulnerable in society to get digital TV.

The culture minister, Ed Vaizey, congratulated Digital UK and said most of the £55m will be used to help the rollout of broadband. "The majority of the underspend will go to fund universal service commitment," he added.

However, he said: "I don't want to commit every penny in case it's something I have to roll back on."

Vaisey congratulated Digital UK and said it provided a role model for the impending switch from analogue to digital that the government wants the radio industry to make.

Digital UK also said research showed that when over-65s switched to digital TV, it gave them the confidence to try out other new technologies.

Around 64% of late converters to digital TV said they now want to try other gadgets.

Personal video recorders such as Sky+ were the most popular digital devices the over-65s were keen to try (36%), with the internet in third place on 28%.

Most of them also said they would rather give up having a mobile phone or going to the cinema than lose their digital television.

Michelle Mitchell, director of the charity Age UK, said: "TV is a really important part of many older people's lives and it's clear that for many, updating to digital has brought not only more choice but also increased confidence when it comes to dealing with technology."

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